Ferrite E cores are one of the most widely recognized shapes, as they are based upon traditional laminated E cores. E cores are fairly inexpensive, and are easy to wind and assemble, with standard bobbins and mounting hardware. Typical applications for E cores include differentia, power and telecom inductors as well as broadband, power, converter and inverter transformers.
One disadvantage of cores is they do not offer self shieldingDimensions of E Cores with Rectangular Cross Section
(based upon Table 2 of IMA Standard Specifications for E, U and I Cores)